B4J Question Strange issue with serial port


Licensed User
Hi everyone , i have a a program that connect with a scales weight, i have no problem doing the conexion, the problem is when the scale is off, but conected , the serial recognize the port but when i try to connect with it and send the comand to obtain the weight i have to posible respons:

1.- the port is busy
2.- waits for ever the response of scales

I tried to catch the error with try and catch but didnt work out.
Also tried to purge the serial conection and tried to close an re-open the conection whitout succes.
Any ideas to be able to recognize if the scales weight its on or off ?
thanks in advance.

Derek Johnson

Active Member
Licensed User
Can you check the CTS (Clear To Send) or DTR (Data Terminal Ready) conditions on the RS232 interface before sending a command? Most devices set one or the other when they are turned on.

J Serial

CTS As Boolean [read only]

DSR As Boolean [read only]

DTR As Boolean [write only]

Even if you can't do this, you could set a timer when you try to use the device and display a message to the user if there is no response within a given time.

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